Running Two Copies of the EXE at Once

Several power users want to be able to run two or more versions of RunDynam in order to take advantage of PCs with several (4 or more) processors. They want to be able to use one copy of RunDynam to solve one dynamic simulation (Base and Policy) and to use another copy of RunDynam to solve a second dynamic simulation at the same time.

We have accommodated this desire as follows.

You can copy your EXE to another name and run the two simultaneously. For example, you can copy RUNDYNAM.EXE to RUNDYNAM2.EXE and run them simultaneously. In order for that to work, these two EXEs must not use the same Temporary or Keep Directories. Accordingly, the name of the Keep Directory and of the default Temporary Directory now has the name of the EXE at the end -- for example

C:\Documents and Settings\pearson\My Documents\gpkeep\RunDynam2Keep

for the KeepDir for RUNDYNAM2.EXE, and

C:\Documents and Settings\pearson\Local Settings\temp\gptemp\RunDynam2

for the default Temporary Directory for RUNDYNAM2.EXE.

If you do this copying and running two EXEs at once, you must be extremely careful since bad things can happen if you aren't sure what you are doing.

If you are not sure, please do not do this. For example, if you are not absolutely clear why the two EXEs must not use the same Temporary or Keep Directories, please do not try this.

If you copy your EXE to another name, RunDynam guarantees that the Keep Directories are different for these EXEs. But RunDynam cannot guarantee that the Temporary Directories are different. It is your responsibility to ensure that the two EXEs are using different Temporary Directories. You can use menu items Check Temporary Directory and Specify Temporary Directory under the Options menu to do this.

As developers, we (somewhat apprehensively) say yes to the power users who need this feature, and we tell those who try it that it is a case of User Beware. We strongly urge all others to keep to the simple and proven strategy of only running one copy of the EXE we supply.

If you copy RUNDYNAM.EXE to RUNDYNAM2.EXE, note that the two programs will have different Keep Directories. Hence, when you change a setting in one (for example, Allow 3 concurrent solves) that setting will not automatically go across to the other EXE since they have different Keep Directories (and hence different INI files).

Note that, even if you copy RUNDYNAM.EXE to RUNDYNAM2.EXE, if you have RUNDYNAM.EXE running and you try to run RUNDYNAM.EXE a second time, you will just be joined into the first RUNDYNAM.EXE session. We have not changed that feature of the EXEs.

URL of this topic: www.copsmodels.com/webhelp/rundynam/hc_twoexes.htm

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